Is it open to the public, or, do you need to be a member of a club at the casino to enter the restaurant?

That is correct. The restaurant is open to the public. Since it is over a casino you can get % off dinner by being a casino rewards member. Food is good, and the dinner rolls are something special.

It is open to the public

The steakhouse is open to the public

JP W, its open to public. Accepts walk-in but best to make a reservation